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Simultaneous Measurement of Turbulence and Particle Kinematics Using Flow Imaging Techniques
Published on: March 12, 2019
Whole atmospheric-turbulence profiling with generalized scidar
Applied Optics
|February 12, 2008
Summary
The generalized scidar technique measures atmospheric turbulence at all altitudes by analyzing stellar scintillation. This study demonstrates its first real-world application, successfully profiling turbulence vertically.
Area of Science:
- Astronomy and Astrophysics
- Atmospheric Physics
Background:
- The standard scintillation, detection, and ranging (SCIDAR) technique is limited to detecting atmospheric turbulence above a few kilometers.
- A generalized SCIDAR (GS) technique has been proposed to overcome this altitude limitation by analyzing scintillation patterns at planes away from the telescope pupil.
Purpose of the Study:
- To report the first experimental implementation of the generalized SCIDAR technique under real atmospheric conditions.
- To validate the GS technique as a vertical profiler for the refractive-index structure constant, C(N)^2(h).
Main Methods:
- The generalized SCIDAR technique was adapted and implemented on the Nordic Optical Telescope and the William Hershel Telescope.
- Measurements involved analyzing the spatial autocorrelation function of scintillation patterns from double stars at various analysis plane positions.
Main Results:
- The study successfully implemented the generalized SCIDAR technique for vertical atmospheric turbulence profiling.
- Experimental results showed good agreement with theoretical predictions for the spatial autocorrelation of scintillation.
Conclusions:
- The generalized SCIDAR technique is effective for measuring atmospheric turbulence profiles from ground level to high altitudes.
- This advancement offers improved capabilities for astronomical site characterization and adaptive optics system optimization.
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